Browsing Preprints aus dem Institut für Mathematik by Title
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20051102BuchDecoding of codes on Picard curves The Picard curves are genus three curves with a non trivial automorphism, which have been intensively studied due their connection with interesting number theoretic problems. In 1989, R. Pellikaan obtained an algorithm ...

20051020BuchDecomposition of a MultiStage Stochastic Programfor Power Dispatch We develop a multistage stochastic program for the optimal dispatch of electric power under uncertain demand in a generation system comprising thermal and pumped storage hydro plants. Based on an abstract duality argument ...

20051102BuchDelay differential equations driven by Lévy processes: stationarity and Feller properties We consider a stochastic delay differential equation driven by a general Lévy process. Both, the drift and the noise term may depend on the past, but only the drift term is assumed to be linear. We show that the segment ...

19961101BuchDensely defined selections of setvalued mappings and applications to the geometry of Banach spaces and optimization

20051102BuchDifferentiable Selections of SetValued Mappings With Application in Stochastic ProgrammingWe consider setvalued mappings defined on a linear normed space with convex closed images in IRn. Our aim is to construct selections which are (Hadamard) directionally differentiable using some approximation of the ...

20051116BuchDifferentiable Selections of SetValued Mappings and Asymptotic Behavior of Random Sets in Infinite Dimensions We consider setvalued mappings acting between two linear normed spaces and having convex closed images. Our aim is to construct selections with directional differentiability properties up to the second order, using certain ...

20051107BuchDifferential algebraic systems anew Linear differential algebraic equations with properly stated leading term are considered via a decoupling into their essential parts. It is shown why for socalled numerically well formulated equations the decoupling and ...

20051104BuchDifferential Algebraic Systems with Properly Stated Leading Term and MNA Equations Differential algebraic equations with properly stated leading term are equations of the form A(x(t),t)(d(x(t),t))'+b(x(t),t)=0 with in some sense wellmatched coefficients. Systems resulting from the modified nodal analysis ...

20051102BuchDifferential Stability of TwoStage Stochastic Programs Twostage stochastic programs with random righthand side are considered. Optimal values and solution sets are regarded as mappings of the expected recourse functions and their perturbations, respectively. Conditions are ...

20110811BuchDiscontinuous Galerkin Finite Element Convergence for Incompressible Miscible Displacement Problems of Low Regularity In this article we analyse the numerical approximation of incompressible miscible displacement problems with a combined mixed finite element and discontinuous Galerkin method under minimal regularity assumptions. The main ...

20060518BuchDiscretisation and Solver Methods for a Model for SolidGasPhase of a Crystal Growth Apparatus. We present discretisation and solver methods for a model for a solidgas phase of a crystal growth aparatus. The modelequations are coupled Eulerian and Heattransferequations with fluxboundary conditions. For more ...

20090702BuchDiscretization methods with analytical characteristic methods for advectiondiffusionreaction equations and 2d applications Our studies are motivated by a desire to model longtime simulations of possible scenarios for a waste disposal. Numerical methods are developed for solving the arising systems of convectiondiffusiondispersionreaction ...

20060101BuchDiscretization methods with analytical solutions for a convectiondiffusiondispersionreactionequation and applications in 2D and 3D for wastescenarios In this part we describe the numerical methods and the results for our discretization methods for system of convectiondiffusiondispersionreaction equation. The motivation came for the simulation of a scenario of a ...

20110811BuchDiscretization methods with analytical solutions for a convectionreaction equation with higherorder discretizations We introduce an improved secondorder discretization method for the convectionreaction equation by combining analytical and numerical solutions. The method is derived from Godunov's scheme, see [Godunov 1959] and [Leveque ...

20060101BuchDiscretizationOptimization Methods for Nonlinear Elliptic Optimal Control Problems with State Constraints We consider an optimal control problem described by a second order elliptic boundary value problem, jointly nonlinear in the state and control, with control and state constraints, where the state constraints and cost ...

20060101BuchDiscretizationOptimization Methods for Nonlinear Elliptic Relaxed Optimal Control Problems with State Constraints. We consider an optimal control problem described by a second order elliptic boundary value problem, jointly nonlinear in the state and control with high monotone nonlinearity in the state, with control and state constraints, ...

20060101BuchDiscretizationOptimization Methods for Nonlinear Parabolic Relaxed Optimal Control Problems with State Constraints We consider an optimal control problem described by a semilinear parabolic partial differential equation, with control and state constraints, where the state constraints and cost involve also the state gradient. Since this ...

19971027BuchDuality Construction of Moduli Spaces

20051104BuchDuality gaps in nonconvex stochastic optimization We consider multistage stochastic optimization models. Logical or integrality constraints, frequently present in optimization models, limit the application of powerful convex analysis tools. Different Lagrangian relaxation ...

19980130BuchEffective solutions of Clebsch and C. Neumann systems We solve in Riemann theta functions the classical Clebsch system and its particular case  the C. Neumann system. Going from a new Lax representation (with rational parameter) we work out the solutions. Separately, using ...